Can no longer boot to Mac OS X

So I have a MacPro (early 2008), running Mountain Lion on an SSD, and I have Windows 8 set up on a second HD with bootcamp. It was working fine until the other day when I was booted in windows and tried installing Ubuntu in a new partition. I had to cancel the installation partway through, but thought I could just reformat the partition after. Now, when I try to hold down OPTION when turning on my computer it will just boot into windows (the boot option screen does not appear). I have also tried restarting in OS X through the bootcamp application in windows but that just restarts the computer in Windows 8.
I am worried I may have messed up the boot record when trying to install Ubuntu, but I can still access all my files on my Mac partition from within Windows so I know it's all there.

If you have an external bootable OS X backup, boot from it if you can and try to repair the Mac partition.
But, I do think you messed up the partition Map, it probably can be repaired but is extremely hard to do so.
If you have a Recovery partition try Holding Command-R at start up and try to repair with Disk Utilities there.

I was able to borrow a USB keyboard from a friend and I can choose to boot from Repair partition or the Mac OS and booting to the Mac OS works however after booting back into windows I am still not able to use the bootcamp application to switch to Mac and I can not get to the boot options screen with my wireless keyboard. I've never had an issue accessing this screen with the wireless keyboard before. Any ideas?

If you can boot back into OS X again, try setting OS X as the main partition in the startup disk pref pane. Also, try resetting the PRAM.

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When I read this the first time I thought,NOOOO, but read it again and the PRAM has the startup disk inside it's setting, now if a PRAM reset does not work there is a way to set it yourself in Single User Mode with "setenv" and the appropriate disk and partition, so that might work.

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